Uranium-216m

Properties and data of the isotope ^216mU.

Contents

See also: List of individual Uranium isotopes (and general data sources).

General data

Name of the isotope:Uranium-216m; U-216mSymbol:^216mU or 216m92UMass number A:216 (= number of nucleons)Atomic number Z:92 (= number of protons)Neutrons N:124Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3478260869565 (= neutron-proton ratio)Neutron excess (N-Z):32Excitation energy:2240(42) keVIsotopic mass:216.02476(3) u (atomic weight of Uranium-216m)Nuclide mass:215.9742973 u (calculated nuclear mass without electrons)Mass excess:23.06379 MeVMass defect:1.769592528 u (per nucleus)Nuclear binding energy:1648.36482228 MeV (per nucleus)
7.63131862 MeV (average binding energy per nucleon)Half-life:0.7 msDecay constant λ:990.21025794278 s^-1Specific activity α:2.760734099206 × 10⁺²⁴ Bq g^-1
74614435113684 Ci g^-1Spin and parity:
(nuclear angular momentum)(8+)

Radioactive Decay

Half-life T_½ = 0.7 ms respectively 7 × 10^-4 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	²¹²Th	> 0 %
Iso	²¹⁶U	?

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
²¹⁶U		4.5 ms	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 124) and isobaric (same nucleon number A = 216) with Uranium-216m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 124	Isobar A = 216
75	¹⁹⁹Re
76	²⁰⁰Os
77	²⁰¹Ir
78	²⁰²Pt
79	²⁰³Au
80	²⁰⁴Hg	²¹⁶Hg
81	²⁰⁵Tl	²¹⁶Tl
82	²⁰⁶Pb	²¹⁶Pb
83	²⁰⁷Bi	²¹⁶Bi
84	²⁰⁸Po	²¹⁶Po
85	²⁰⁹At	²¹⁶At
86	²¹⁰Rn	²¹⁶Rn
87	²¹¹Fr	²¹⁶Fr
88	²¹²Ra	²¹⁶Ra
89	²¹³Ac	²¹⁶Ac
90	²¹⁴Th	²¹⁶Th
91	²¹⁵Pa	²¹⁶Pa
92	²¹⁶U	²¹⁶U